Multiple-component systems vessel

Over the years, many failures of plant systems and components have been attributed to solenoid-operated valve (SOV) problems. Several events have occurred in which SOV failures affected redundant safety components, multiple trains of safety systems, or multiple safety systems. SOVs are in wide-spread use in each nuclear power facility. They are used in safety-related systems indirectly as pilot operators working with control system fluid (such as pneumatic or hydraulically operated isolation valves) and directly in fluid systems (such as to vent the reactor vessel head or to supply air to the starting system for emergency diesel generators). Many SOVs are also used in non-safety-related systems that can significantly affect safety systems (such as plant instrument air drier systems). 

This mass difference between the single and multiple Brayton systems can be spent to reduce the operating temperature of the primary plant, which in turn reduces creep concerns in the fuel elements, the core stmctural components, the reactor vessel, the loop piping and the turbine wheel. Reducing the temperature of the plant by 100K would increase the material creep capability, in terms of applied stress, by about a factor of 2. Chemical compatibility would also be improved at this lower temperature. Evaluation of the acceptability of lower operating conditions on core material embrittlement would be required for consideration of this reduced temperature case. 

Pressure surges in liquid service Violent, multiple closing cycles cause liquid water hammer and place undue stress on companion piping, piping supports, internal components in pressure vessels, metering systems, and so on. 

The aluminum fires experienced in the simulated rocket motor testing at Munster were attributed to the use of too much aluminum. More extensive experience in Taiwan was cited as an indication that aluminum fires will not be an issue at BGCAPP. The only aluminum components of rocket motors are the fins the bodies are steel. Also, the multiple vessel rotations used to remove scrap from the detonation chamber are considered by the manufacturer to be part of the normal operation of the system. 

A low-cost nickel-hydrogen system proposed by Eagle Picher is based on the multiple cell per single battery pressure vessel concept. Additional system cost reduction is proposed through use of standardized components, ease of manufacture and an inherent design versatility able to meet various voltage and capacity requirements with only minor modifications. 

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